Compressor for refrigerating systems



April 5, 1949.

A. P. ANDERSON COMPRESSOR FOR REFRIGERATING SYSTEMS 2 Sheets-Sheet lFiled Sept. 17, 1945 April 5, 1949. A. P. ANDERSON COMPRESSOR FORREFRIGERATING SYVSTEMS 2 Sheets-Sheet 2 Filed Sept. 17, 1945 PatentedApr. 5, 1949 B. BEFRIGERATIN G SYSTEMS August P. Anderson, Goshen, Ind.

Application September 17, 1945, Serial No. 616,882 5 Claims. (Cl.230-175) COMPRESSOR F The invention relates to compressors forrefrigerating systems.

One object of the invention is to provide a compressor of the radialpiston-type in which swinging movement is imparted to cylinders so theyautomatically function to control the intake to, and exhaust of fluidfrom the cylinders, for the compression of fluid by the piston.

Another object of the invention is to eliminate, from compressors of theradial .piston type, vthe conventional intake and discharge valves forthe cylinders which, in use, are subject to wear and leakage, becomenoisy, are sometimes rendered leaky by scale, metal cuttings, carbon,grit and the like in the uid being compressed.

Another object of the invention is to provide a compressor of the radialpiston type for refrigating systems which comprises three or moreradially movable pistons, which is simple in c'onstruction, light inweight, includes interchangeable parts, is balanced, and free fromvibration.

Another object of the invention is to provide a compressor of this typewhich is simple and compact in construction and eicient in operation.

Another object of the invention is to provide a compressor of this typewhich can be produced and operated at low cost.

Other objects of the invention will appear from the detaileddescription.

The invention consists in the several features hereinafter set forth andmore particularly dened by claims at the conclusion hereof.

In the drawings:

Fig. 1 is a central longitudinal section of a compressor embodying theinvention taken on line l-l of Fig. 2.

Fig. 2 is a perspective of one of the compressor-cylinders.

Fig. 3 is a view of a portion of the face of the stationary head engagedby the cylinders.

Fig. 4 is a section illustrating one of the exhaust ports in the casing.Y

Fig. 5 is a section illustrating one of the intake ports in the casing.

Fig. 6 is a section taken on line 6-6 of Fig. 1.

Fig. 7 is a diagrammatic view of one of the compressor pistons andcylinders and the circular path of the axis of the pivot between thepis-` ton and the eccentric ring, illustrating the angle of a cylinderand its piston at the end of a compression stroke of the piston, andrelative positions of the cylinder-port and the inlet and exhaust ductsin the crank-case at the end of the compression stroke.

Fig. 8 is a similar view illustrating the angular pitioniof acompressor-cylinder and its piston at the middle of a suction stroke ofthe piston and the relative positions of the cylinder-port and the inletand exhaust ducts in the crank-case when the piston is at the middle ofits exhaust stroke.

Fig. 9 is a similar view illustrating the angular position of acompressor-cylinder and its piston at the end of the suction stroke ofthe piston and .the relative positions of the cylinder-port and theinlet and exhaust ducts in the crank-case, at the end of said suctionstroke.

Fig. 10 is a similar view illustrating the angular position of thecylinder and its piston in the middle of a compression stroke and therelative positions of the cylinder-port and exhaust and inlet ducts inthe crank-case when thepiston is in the middle of said compressionstroke.

The compressor comprises a stationary casing which may be supported inany vsuitable manner for housing the electric motor I6 for driving theAcompressor. This casing includes a cylindrical section I0 having anintegral cross-wall or head I I and a removable upper head l2, whichprovide a sealed enclosure for the electric motor I6. The casing alsocomprises a crank-case section which includes a cylindrical wall orcrank-case Il with an integral lower-end wall which, with the head Il,form a housing for the operating elements of the compressor, and isadapted to retain a column of lubricating oil. The upper-end of thecrankcase is provided with a flange I9 which is removably secured bybolts 20 to a flange 2| around the head II for access to the compressor.A head or frame 28 is stationarily supported in the crankcase inlongitudinally spaced relation from head Il, by a series of spacer bolts30, the upper ends of which are screw-threaded into head il. A shaft 23of the rotor of electric motor I6 is journalled in a bushing 24 in a hub25 on head Il and a bushing 26 which extends through and is fixed in thehub of head 28. A thrust-bearing 29 is provided for shaft 23.

Shaft23 extends through the head I i and into the head 28 and has keyedthereto, between said heads, an eccentric 44 for operating a series ofradial pistons. Eccentric 44 is provided with a hub 45 which is securedon shaft 23 by a nut 46 which clamps said hub between a collar 41engaged by said nut and a collar 48 which engages a shoulder on saidshaft. A weight 44a is integrally formed with eccentric 44 and functionsas a counter-balance. The eccentric 44 fits in a ring 4i for operatingthe compressor pistons by power from the motor I6.

The compressor is exemplified with a series of 3 three radial cylinders32 which are symmetrically disposed around the axis, of shaft 23 and areconfined for pivotal movement between the confronting faces of heads 26and II. Pistons 39 are axially slidable in said cylinders 32,respectively. Each cylinder 32 is provided on its opposite sides withco-axial trunnions 33 which are journalled in sockets 34 in heads Il and23, for pivotally supporting the cylinder to swing in a plane parallelwith the plane of rotation of eccentric 44 or transversely to the axisof shaft 23. Each piston has a rigid or integral stem which is pivotallyconnected to ring 4I which nts around and is operated by eccentric 44.Pins 42, which pivotally connect ring 4I and pistons 39, are operated bythe eccentric 44 to impart movement to the pistons 39 for moving themaxially in cylinders 32 'for suction and compression strokes and tooperate the pistons angularly for swinging the cylinders impartingcompound angular and axial movement to the pistons which imparts pivotalmovement to the cylinders. y

A plunger 39 is slidably tted in a pivoted I cylindrical guide 39b whichis provided with trunnions 39 which are journalled Inco-axial sockets'in heads II and 26. Plunger 39a is provided with a rigid or integralstem 43 which is secured to ring 4I by rivets 46'. Plunger 39B and thepivoted cylinder 39h constitute means for controlling the angularmovement of ring 4I relatively to the axis of shaft 23 to cause thepistons 39 of the compressor and cylinders 32 to swing 0n the axes oftrunnions 33 and control the pivotal movement of the cylinders-in thecrank-case, to impart predetermined compounded sliding and pivotalstrokes to pistons 39, and pivotal strokes' to cylinders 32.

Each compressor cylinder 32 is provided with a port 56 in its side whichfaces the head II. through which fluid alternately passes into and isdischarged from the cylinder from intake and exhaust ducts formedin thecontiguous face of head II. Each cylinder 32 is provided with anintegral pad 32a having a face which slidably fits against the face of apad 35 formed on the contiguous face of head Ii. The faces of pads 34 oncylinders 32 are pressed into wiping contact with the contiguous facesof pads 35 by springs 36 to maintain a Huid-tight nt between said faces.Springs 36 are confined in the trunnion-sockets 344 in head 26 andengage the trunnions 33 in said head to urge the cylinders 32 intocontact with the pads 35 on head I I. A similar spring may be providedfor cylindrical guide 39h.

The low pressure fluid or gas from the suction line of a refrigeratingsystem is delivered into the crank-case by a pipe 52 which is connectedto head II and communicates with the chamber in crank-case I1. Head IIis provided with an angular intake duct I for each cylinder 32 whichcommunicates with the chamber in the crankcase and terminates in theface of a pad 35 on said head, for communicatively connecting cylinder--port 56 to receive fluid during the suction stroke of the piston 39. Adischarge or high pressure Aduct 54 is formed inA head Il for eachcylinder 32 and is communicatively connected with one of thecylinder-ports 50 during the out pressure stroke of a piston 39.Discharge ducts 54 for all of the cylinders 32 are communicativelyconnected to branches of a header 55 which is connected to delivercompressed gas to the condenser of the refrigerating system. Each branchof header 55 includes a check-valve 56. The swinging movement ofcylinders 32 are utilized to produce a valve action between the I I foralternately controlling. through ports 50.

' the intake of gas from a duct 5I and the discharge of compressed gasto a duct 5,4. The swinging movements of cylinders 32 also produce a.wiping action between the faces of pads 34 and 35 which tends to keepthe contiguous faces free from grit or dirt.

The lower portion of the crank-case il is adapted to retain, or serveasa sump for, a supply of oil for lubricating the bearings of thecompressor. A vane type pump 66 includes an impeller 6I which is securedto and driven by the lower end of shaft 23 and a casing 62 for theimpeller which is secured by screws 63 to the lower end of head 26. Theintake 64 for the oil extends below the level of the column of oilmaintained in the crankcase I1. An outlet pipe 65 for oil from casing 62is connected to a duct 61 in head II for lubricating the bearing inbushing 24 for shaft 23 and to a duct 66 in head 26 for lubricating thebearing in bushing 2.6 for said shaft. Oil which is carried upwardlythrough bushing 24 passes to ducts 69 in head II for lubricating thebearings for the upper trunnions 33, and leaks back into the crank-case.Ducts `6I! in head 28 conduct oil from the column in the Acrank-case tothe bearings for the lower trunnions 3,3.

The operation of the compressor will be as follows: eccentric 44 isrotated continuously in one direction by shaft 23 which is driven by theelectric motor I6 and will operate ring 4I to impart axial sliding andoscillatory movement to the pistons 33 which will im part oscillatingmovement to cylinders 32. During each rotation of eccentric 44, plunger39, operating inthe pivoted guide 39, will control the angular movementof'ringliY Y around said eccentric and the movement of pins 42. Theoscillatory movement of the cylinders 32 will move alternately theirports 56 for intake of gas from ducts 5I and for the discharge ofcompressed gas through ports 50 and ducts 54. The angular movement ofring 4I on eccentric 44 is controlled by the fixed connection betweensaid ring and plunger-39a which is slidable in cylindrical guide 39bvwhich is pivotally movable in the sockets for trunnions 39e. Theseelements cause each of the axes of `pins 42 between ring 4I and pistons39 to travel in circles indicated by the dotted circle marked X in Figs.'l to 10. During each revolutiony ofeccentric 44, the ring M will beoperated to impart compound reciprocating Vand .angular intake andcompression strokes to the pistons 39 in rotative succession. Theangular movement of the cylinders 32 produced by pistons 39 from ring 4Iwill, during each rotation of eccentric 44, control communicationthrough each vcylinder-port 5t with its intake duct 5I and its dischargeduct 54. Assuming the -pistons 39 to be at the end of its outstroke, asillustrated in Fig. 7, the port 50 will be disposed between itsassociated ducts 5I and 54 and closed. Ring 4I, during the inwardmovement or suction stroke of piston 39, will swing each cylinder 32 toregister its port 56 with the intake duct 5I to admit iiuid into thecyinder 32, as illustrated in Fig. 8. When the piston 39 reaches the endof its suction stroke, as illustrated in Fig. 9, cylvinder-port 59 willagain be closed. During the succeeding outstroke of pistons 39, eachcylinder 32 will be shifted angularly, as illustrated in Fig. .10, andits cylinder-port 50 will be in communication with its associateddischarge'duct 54 and discharge the uid under compression to the header55. Each piston 39 will be operated in rocylinders 32 and head tativesuccession to produce a substantially constant outflow of compressediluid.

In this operation,` this piston 39 which is connected to ring 4Idiametrically opposite the guide plunger 39a and the cylinder 32 forsaid piston, if the pin 42 connecting said piston and ring is spaced thesame radial distance from the axis of shaft 23 as the other pins 42,would be shifted a greater angular extent than the pins 42 for the otherpistons 39. To compensate for this variation, the axis of the trunnions39c for the cylindrical guide 39b and the axis of the diametricallyopposite cylinder 32 are spaced a somewhat greater distance from theaxis of shaft 23 than the tr'unnions for the other cylinders. Thisresults in imparting angular movement of the same degree to the outerends of all the cylinders 32 and makes it possible to provide intakeducts and exhaust ducts equi-distantly spaced apart, for producing thesame relctive .movement between the cylinder-ports 50 and the intakeducts 5I and exhaust ducts 54 for all of the cylinders 32. In thismanner, the pivotal or angular movements of the cylinders 32 impartedthereto by the pistons 39 and eccentric 44, the ring 4l and pistons 39will automatically control the intake of the fluid into the cylindersand the discharge of the compressed uid from the cylinders in rotativesuccession.

The invention exemplifies a compressor of the radial piston and cylindertype in which the :flow of gas to and from the cylinders isautomatically controlled Without conventional poppet, or slide` valves.The compressor is simple and compact in construction and the operatingparts are automatically lubricated. Upon removal of the crankcase I1from the casing section which houses the electric motor, the compressorparts become readily accessible for repair or replacement.

While the invention has been described and is particularly advantageousfor use with refrigerating gases, it is obvious that it may be used forother purposes. The invention is also applicable -to compressors withany suitable number of cylinders and pistons.

The invention is not to be understood as limited to the detailsdescribed, since these may be modified Within the scope of the appendedclaims without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire tosecure by Letters Patent is:

l. A compressor comprising a series of pivotally mounted cylinders,pistons axially slidable in and pivotally movable for pivotaly shiftingthe cylinders, a driven eccentric, a ring on the eccentric, meansincluding an element rigid with and for controlling the angular movementof the ring for imparting sliding and pivotal strokes to the i pistonsfor pivotally shifting the cylinders, and means controlled by thepivotal movement of the cylinders for controlling the intake and exhaustof uid for compression in the cylinders by the pistons.

2. A compressor comprising a casing adapted to vretain oil and a head, adriven shaft extending through the head, an eccentric on said shaft, andin the casing, a ring on said eccentric, a second head mounted in thecasing in spaced relation to the nrst head, cylinders disposed between'the heads and provided with trunnions for supporting the cylinders forpivotal movementand with faces iitting against the rst head, springsmounted in the second head for pressing the cylinders against the firsthead, pistons axially slidable in the cylinders and provided with fixedstems .pivotally connected to the ring, means for controlling theangular movement of the ring to impart axial movement of the pistons inthe cylinders and their pivotal movement for swinging the cylindersbetween said heads, and intake and exhaust ducts in said rst head, thecylinders being provided with ports movable between said ducts forcontrolling the flow of fluid between said ducts and the cylinders.

3.' A compressor comprising: a casing, a series of cylinders pivotallymounted in the casing, pistons axially slidable in and pivotally movablewith the cylinders, a driven eccentric, a ring journalled on theeccentric, circumferentially spaced pivotal connections between the ringand the pistons, respectively, means for limiting the angular movementof the ring on the eccentric to control said pivotal connections forimparting reciprocating movement to the pistons, and means controlled bythe pivotal movement of the cylinders for controlling the intake andexhaust of -fiuid for compression in the cylinders by the pistons.

4. A compressor comprising: a casing, a series of cylinders pivotallymounted in the casing, pistons axially slidable in and pivotally movablewith the cylinders, a driven eccentric, a ring journalled on theeccentric, circumferentially spaced pivotal connections between the ringand the pistons, respectively, means for limiting the angular movementof the ring on the eccentric to control said pivotal connections forimparting reciprocating movement to the pistons, said limiting meansincluding a stem rigid with and projecting outwardly from the ring, andmeans controlled by the pivotal movement of the cylinders forcontrolling the intake and exhaust of fluid for compression in thecylinders by the pistons.

5. A compressor comprising: a casing, a series of cylinders pivotallymou/ted in the casing, pistons axially slidable in and pivotally movablewith the cylinders, a driven eccentric, a ring journalled on theeccentric, circumferentially spaced pivotal connections between the ringand the pistons, respectively, means for limiting the angular movementof the ring on the eccentric to control the pivotal connections forimparting reciproeating movement to the pistons, said limiting meansincluding a stem rigid with the ring and a guide pivotally mounted inthe casing and in which the stem is slidable, and means controlled bythe pivotal movement of the cylinders for controlling the intake andexhaust of fluid for compression. in the cylinders by the pistons.

AUGUST P. ANDERSON.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,675,546 Green July 3, 19281,703,108 Hvid Feb. 26, 1929

